Detachable blades for a ceiling fan

ABSTRACT

A detachable blade and support assembly for a ceiling fan includes a support having an insert groove, a blade having an insert end portion inserted into the insert groove and having two retaining grooves formed respectively formed in two opposite side surfaces, and a mounting unit connecting the blade to the support. The mounting unit includes two side resilient members disposed on the support and having engaging portions engaging respectively and fittingly the retaining grooves in the support to retain releaseably the insert end portion of the blade in the insert groove in the support, a centrifugal resilient member for preventing the engaging portions of the side resilient members from movement in the retaining grooves in the blade.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priorities of Taiwanese Application No. 103206822, filed on Apr. 18, 2014, the entire disclosure of which is hereby incorporated by reference.

FIELD

This disclosure relates to a fan, and more particularly to detachable blades for a ceiling fan.

BACKGROUND

Referring to FIGS. 1 and 2, a conventional detachable blade and support assembly 10 for a ceiling fan disclosed in U.S. Pat. No. 6,171,059 includes a support 11, a blade 12, a mounting unit 13, and a cover plate 14. The support 11 includes an insert block 111, two insert grooves 112, and two receiving grooves 113 formed respectively in two opposite side portions of the insert block 111 and in spatial communication with the insert grooves 112. The blade 12 has an opening 121 formed in an end thereof, and two retaining grooves 122 located respectively at two sides of and in spatial communication with the opening 121. The mounting unit 13 includes two springs 131 disposed respectively within the receiving grooves 113, and two retaining blocks 132 disposed respectively within the receiving grooves 113 and biased by the springs 131 to project outwardly from the receiving grooves 113, respectively. The cover plate 14 is fastened to a top surface of the insert block 111.

In assembly, it is only necessary to move the blade 12 into the support 11 such that the insert block 111 of the support 11 is engaged into the opening 121 in the blade 12. During engagement of the insert block 111 into the opening 121, the retaining blocks 132 are biased to engage respectively the retaining grooves 122 in the blade 12, thereby completing the assembly of the blade 12 to the support 11 and preventing removal of the blade 12 from the support 11.

A problem is encountered by such an assembly. To ensure that the retaining blocks 132 can move into the retaining grooves 122, a clearance must be left between each of the retaining blocks 132 and a wall of the blade 12 defining the corresponding retaining groove 122. Hence, during rotation of the ceiling fan, due to centrifugal force, the retaining blocks 132 move within the retaining grooves 22, thereby resulting in sway of the blade 12 and increased noise occurred when the blade 12 rotates. In addition, U.S. Pat. No. 686,211 discloses a similar ceiling fan that has the same problem.

SUMMARY

Therefore, an object of this disclosure is to provide a detachable blade and support assembly for a ceiling fan, which can reduce sway of the blade and noise occurred when the blade rotates.

According to this disclosure, there is provided a detachable blade and support assembly for a ceiling fan comprising:

a support having an insert groove;

a blade having an insert end portion that is inserted into the insert groove, and a free end portion that is opposite to the insert end portion, the insert end portion having an end surface, two opposite side surfaces extending respectively from two opposite sides of the end surface, and two retaining grooves formed respectively formed in the side surfaces; and

a mounting unit including two side resilient members disposed on the support and having engaging portions engaging respectively and fittingly the retaining grooves in the support to retain releaseably the insert end portion of the blade in the insert groove in the support, a centrifugal resilient member disposed between the end surface of the blade and the support so as to prevent the engaging portions of the side resilient members from movement in the retaining grooves in the blade.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of this disclosure will become apparent in the following detailed description of a preferred embodiment of this disclosure, with reference to the accompanying drawings, in which:

FIG. 1 is a top view of a conventional blade and support assembly;

FIG. 2 is a fragmentary top view of the conventional blade and support assembly;

FIG. 3 is a perspective view of an improved ceiling fan including the preferred embodiment of a detachable blade and support assembly according to this disclosure;

FIG. 4 is a partly exploded perspective view of the improved ceiling fan;

FIG. 5 is a fragmentary, exploded perspective view of the preferred embodiment;

FIG. 6 is a fragmentary, schematic top view of the preferred embodiment, illustrating that, during assembly, a portion of a blade is inserted into a support;

FIG. 7 is a view similar to FIG. 6 but illustrating that, during assembly, the blade is moved from the position shown in FIG. 6 toward a centrifugal resilient member;

FIG. 8 is a view similar to FIG. 7 but illustrating that the preferred embodiment is in a fully assembled state and the blade is biased by the centrifugal resilient member so as to prevent movement of the blade relative to the support; and

FIG. 9 is a view similar to FIG. 8 but illustrating how the blade is removed from the support.

DETAILED DESCRIPTION

Referring to FIGS. 3, 4, and 5, the preferred embodiment of a detachable blade and support assembly according to this disclosure is adapted to use in a ceiling fan that includes a suspension unit 20, a motor 30, and a plurality of blades 50. The suspension unit 20 includes a suspending frame 21. The motor 30 is mounted to the suspension unit 20, and includes a rotating shaft 31. The detachable blade and support assembly includes a support 40, a blade 50, a mounting unit 60, and a foolproof unit 70.

The support 40 is driven by the motor 30, and includes a support body 41 having an insert groove 410, a base wall 411, an outer peripheral wall 412 extending upwardly from an outer periphery of the base wall 411, and an inner peripheral wall 413 extending upwardly from an inner periphery of the base wall 411. The outer peripheral wall 412 has a hole 414 formed therethrough.

The support 40 further includes a top cover 42 disposed at a top end thereof. The rotating shaft 31 of the motor 30 is connected fixedly to the top cover 42.

The blade 50 has an insert end portion 51 and a free end portion that is opposite to the insert end portion. The insert end portion 51 has an end surface 511, two opposite side surfaces 512 extending respectively from two opposite sides of the end surface 511, two retaining grooves 53 formed respectively in the side surfaces 512, and two disassembly grooves 54.

Each retaining groove 53 is triangular, and is defined by a shoulder surface 531 perpendicular to the corresponding side surface 512, and an inclined surface 532 inclined relative to the corresponding side surface 512, such that the corresponding disassembly groove 54 is formed in the inclined surface 532.

The blade 50 is made of plastics or wood. The insert end portion 51 is flat. The free end 52 is not flat.

The mounting unit 60 includes two guide blocks 61, two first locking posts 62, two side resilient members 63, a rib 65, a fixed post 66, a centrifugal resilient member 67, and a cover plate 69.

The two guide blocks 61 are fixed on the base wall 411, extend from the outer peripheral wall 412 toward the inner peripheral wall 413, and are spaced apart from the inner peripheral wall 413, such that the insert groove 410 is defined between the guide blocks 61. Each guide block 61 has a vertical groove 611 permitting the corresponding side resilient member 63 to be inserted thereinto, and a disassembly hole 612 aligned with the corresponding disassembly groove 54.

Each first locking post 62 is disposed fixedly on the base wall 411, and is adjacent to the outer peripheral wall 412 and the corresponding guide block 61.

Each side resilient member 63 is configured as a spring plate, and has a vertical plate portion 631 inserted into and fixed within the vertical groove 611 in the corresponding guide block 61, a hole 632 formed through the vertical plate portion 631, and a movable plate portion 633 extending from the vertical plate portion 631 and into the hole 632 and constituting an engaging portion for engaging fittingly the corresponding retaining groove 53. to retain releaseably the insert end portion 51 of the blade 50 in the insert groove 410 in the support 40. Each movable plate portion 633 has an inclined section 634 extending from the vertical plate portion 631 into the insert groove 410 in the support 40, an intermediate section 635 extending from an end of the inclined section 634 in a direction away from the insert groove 410, and a free end section 636 extending from an end of the intermediate section 635 distal from the inclined section 634 in a direction away from the inclined section 634.

Each side resilient member 63 further has a lug 637 extending from a top end of the corresponding vertical plate portion 631 and fastened to the corresponding first locking post 62.

The rib 65 is fixed on the base wall 411, and is adjacent to the inner peripheral wall 413.

The fixed post 66 is fixed on the base wall 411, and is adjacent to the rib 65.

The centrifugal resilient member 67 is disposed between the end surface 511 of the blade 50 and the support 40 so as to prevent the engaging portions 633 of the side resilient members 63 from movement in the retaining grooves 53 in the blade 50.

In this embodiment, the centrifugal resilient member 67 is configured as a curved spring plate, and has a mounting end 671 sleeved rotatably on the fixed post 66, a free end 673 in contact with the rib 65, and a blade engaging section 672 disposed between the mounting end 671 and the free end 673.

The rib 62 is formed with two second locking posts 68 that are adjacent to the inner peripheral wall 413.

The cover plate 69 is fastened to the two second locking posts 68, and is disposed directly above the centrifugal resilient member 67 for preventing upward removal of the centrifugal resilient member 67 from the fixed post 66.

The foolproof unit 70 includes a recess 71 formed in the outer peripheral wall 412 and in spatial communication with the hole 414, and a protrusion 72 disposed on a top surface of the insert end portion 51.

With particular reference to FIGS. 5 and 6, to assemble the blade 50 to the support 40, it is only necessary to insert the insert end portion 51 of the blade 50 through the hole 414 and into the insert groove 410 in a direction (II). During movement of the insert end portion 51 in the insert groove 410, the end surfaces 511 come into contact and push the inclined sections 634 of the side resilient members 63 to move the free end sections 636 away from each other, as shown FIG. 7. As soon as the retaining grooves 53 are aligned with the movable plate portions 633, the movable plate portions 633 are biased to engage the retaining grooves 53, as shown in FIG. 8, thereby preventing removal of the blade 50 from the support 40. At this time, the blade engaging portion 672 of the centrifugal resilient member 67 biases the end surface 511 of the insert end portion 51 to move away from the center of the ceiling fan, that is, in a direction opposite to the direction (II). Hence, the shoulders 531 are pressed against the intermediate sections 635, so as to maintain contact between the blade 50 and the side resilient members 63 in the direction opposite to the direction (II).

With particular reference to FIG. 9, by inserting a tool (T) into the disassembly hole 612 and the disassembly groove 54, the movable plate portions 633 can be disengaged from the retaining grooves 53, thereby allowing the blade 50 to be removed from the support 40 in a direction (III).

The detachable blade and support assembly of this disclosure has the following advantages:

-   -   1. Due to the presence of the centrifugal member 67, movement of         the blade 50 relative to the support 40 can be prevented,         thereby diminishing sway of the blade 50 and noise when the         blade 50 rotates.     -   2. Due to the presence of the foolproof unit 70, assembly         mistakes can be reduced, so as to promote the assembling         efficiency.     -   3. Due to the presence of the disassembly hole 62 and the         disassembly groove 54, the blade 50 is easy to be removed from         the support 40.

While the disclosure has been described in connection with what is (are) considered the exemplary embodiment(s), it is understood that this disclosure is not limited to the disclosed embodiment(s) but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements. 

What is claimed is:
 1. A detachable blade and support assembly for a ceiling fan comprising: a support having an insert groove; a blade having an insert end portion that is inserted into the insert groove, and a free end portion that is opposite to the insert end portion, the insert end portion having an end surface, two opposite side surfaces extending respectively from two opposite sides of the end surface, and two retaining grooves formed respectively formed in the side surfaces; and a mounting unit including two side resilient members disposed on the support and having engaging portions engaging respectively and fittingly the retaining grooves in the support to retain releaseably the insert end portion of the blade in the insert groove on the support, a centrifugal resilient member disposed between the end surface of the blade and the support so as to prevent the engaging portions of the side resilient members from movement in the retaining grooves in the blade.
 2. The detachable blade and support assembly as claimed in claim 1, wherein the centrifugal resilient member is configured as a curved spring plate, the mounting unit further including a rib extending from the support, and a fixed post fixed on the support and adjacent to the rib, the centrifugal unit having a mounting end sleeved rotatably on the fixed post, a free end in contact with the rib, and a blade engaging section disposed between the mounting end and the free end.
 3. The detachable blade and support assembly as claimed in claim 1, wherein the support further has a base wall, an outer peripheral wall extending upwardly from the base wall, a hole formed through the outer peripheral wall and permitting the insert end portion of the blade to extend therethrough, and two guide blocks fixed on the base wall and defining the insert groove therebetween, each of the guide blocks having a vertical groove that permits a respective one of the side resilient members to be inserted thereinto.
 4. The detachable blade and support assembly as claimed in claim 3, wherein each of the side resilient members is configured as a spring plate, and has a vertical plate portion inserted into and fixed within the vertical groove in a respective one of the guide blocks, a hole portion formed through the vertical plate portion, and a movable plate portion extending from the vertical plate portion and into the hole portion and having a retaining end section that is engaged in a respective one of the retaining grooves in the blade and that is removable from the respective one of the retaining grooves to allow removal of the blade from the support, the movable plate portions of the side resilient members constituting the engaging portions, the movable plate portion of each of the side resilient members having an inclined section extending from the vertical plate portion into the insert groove in the support, and an intermediate section extending from an end of the inclined section in a direction away from the insert groove, the retaining end section extending from an end of the intermediate section distal from the inclined section in a direction away from the inclined section.
 5. The detachable blade and support assembly as claimed in claim 4, wherein the blade has two opposite inclined surfaces each formed with a disassembly groove, each of the guide blocks having a disassembly hole aligned with the disassembly groove in a respective one of the inclined surfaces. 